Identification of \u3ci\u3eVibrio\u3c/i\u3e Isolates by a Multiplex PCR Assay and \u3ci\u3erpoB\u3c/i\u3e Sequence Determination

Vibrio, a diverse genus of aquatic bacteria, currently includes 72 species, 12 of which occur in human clinical samples. Of these 12, three species—Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus—account for the majority of Vibrio infections in humans. Rapid and accurate identification of Vibrio species has been problematic because phenotypic characteristics are variable within species and biochemical identification requires 2 or more days to complete. To facilitate the identification of human-pathogenic species, we developed a multiplex PCR that uses species-specific primers to amplify gene regions in four species (V. cholerae, V. parahaemolyticus, V. vulnificus, and V. mimicus). The assay was tested on a sample of 309 Vibrio isolates representing 26 named species (including 12 human pathogens) that had been characterized by biochemical methods. A total of 190 isolates that had been identified as one of the four target species all yielded results consistent with the previous classification. The assay identified an additional four V. parahaemolyticus isolates among the other 119 isolates. Sequence analysis based on rpoB was used to validate the multiplex results for these four isolates, and all clustered with other V. parahaemolyticus sequences. The rpoB sequences for 12 of 15 previously unidentified isolates clustered with other Vibrio species in a phylogenetic analysis, and three isolates appeared to represent unnamed Vibrio species. The PCR assay provides a simple, rapid, and reliable tool for identification of the major Vibrio pathogens in clinical samples, and rpoB sequencing provides an additional identification tool for other species in the genus Vibrio

Enterotoxin-producing Escherichia coli O169:H41, United States

From 1996 to 2003, 16 outbreaks of enterotoxigenic Escherichia coli (ETEC) infections in the United States and on cruise ships were confirmed. E. coli serotype O169:H41 was identified in 10 outbreaks and was the only serotype in 6. This serotype was identified in 1 of 21 confirmed ETEC outbreaks before 1996

Identification of \u3ci\u3eVibrio\u3c/i\u3e Isolates by a Multiplex PCR Assay and \u3ci\u3erpoB\u3c/i\u3e Sequence Determination

Vibrio, a diverse genus of aquatic bacteria, currently includes 72 species, 12 of which occur in human clinical samples. Of these 12, three species—Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus—account for the majority of Vibrio infections in humans. Rapid and accurate identification of Vibrio species has been problematic because phenotypic characteristics are variable within species and biochemical identification requires 2 or more days to complete. To facilitate the identification of human-pathogenic species, we developed a multiplex PCR that uses species-specific primers to amplify gene regions in four species (V. cholerae, V. parahaemolyticus, V. vulnificus, and V. mimicus). The assay was tested on a sample of 309 Vibrio isolates representing 26 named species (including 12 human pathogens) that had been characterized by biochemical methods. A total of 190 isolates that had been identified as one of the four target species all yielded results consistent with the previous classification. The assay identified an additional four V. parahaemolyticus isolates among the other 119 isolates. Sequence analysis based on rpoB was used to validate the multiplex results for these four isolates, and all clustered with other V. parahaemolyticus sequences. The rpoB sequences for 12 of 15 previously unidentified isolates clustered with other Vibrio species in a phylogenetic analysis, and three isolates appeared to represent unnamed Vibrio species. The PCR assay provides a simple, rapid, and reliable tool for identification of the major Vibrio pathogens in clinical samples, and rpoB sequencing provides an additional identification tool for other species in the genus Vibrio

Identification of Vibrio Isolates by a Multiplex PCR Assay and rpoB Sequence Determination

Vibrio, a diverse genus of aquatic bacteria, currently includes 72 species, 12 of which occur in human clinical samples. Of these 12, three species—Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus—account for the majority of Vibrio infections in humans. Rapid and accurate identification of Vibrio species has been problematic because phenotypic characteristics are variable within species and biochemical identification requires 2 or more days to complete. To facilitate the identification of human-pathogenic species, we developed a multiplex PCR that uses species-specific primers to amplify gene regions in four species (V. cholerae, V. parahaemolyticus, V. vulnificus, and V. mimicus). The assay was tested on a sample of 309 Vibrio isolates representing 26 named species (including 12 human pathogens) that had been characterized by biochemical methods. A total of 190 isolates that had been identified as one of the four target species all yielded results consistent with the previous classification. The assay identified an additional four V. parahaemolyticus isolates among the other 119 isolates. Sequence analysis based on rpoB was used to validate the multiplex results for these four isolates, and all clustered with other V. parahaemolyticus sequences. The rpoB sequences for 12 of 15 previously unidentified isolates clustered with other Vibrio species in a phylogenetic analysis, and three isolates appeared to represent unnamed Vibrio species. The PCR assay provides a simple, rapid, and reliable tool for identification of the major Vibrio pathogens in clinical samples, and rpoB sequencing provides an additional identification tool for other species in the genus Vibrio

Case–control study to determine risk factors for diarrhea among children during a large outbreak in a country with a high prevalence of HIV infection

SummaryObjectivesBetween January and March of 2006, over 35 000 diarrhea cases and 532 deaths were reported among children aged <5 years in Botswana. We conducted an investigation to characterize the outbreak, identify risk factors for diarrhea, and recommend control strategies.MethodsWe enrolled children <5 years of age presenting to the emergency department between March 2 and March 20, 2006. Cases had ≥3 loose stools per day and no antecedent diarrhea among household members. Controls had had no diarrhea since January 1, 2006. We conducted a multivariate logistic regression analysis controlling for socioeconomic status, age, and maternal HIV status.ResultsForty-nine cases with median age of 12 months (range 0–45 months) and 61 controls with median age of 24 months (range 0–59 months) were enrolled; 33 (30%) were born to HIV-positive mothers. Case-parents were more likely to report storing household drinking water (adjusted odds ratios (AOR) 3.9, 95% confidence interval (CI) 1.2–15.7). Lack of hand washing after using the toilet or latrine (AOR 4.2, 95% CI 1.1–20.4) was more likely to be reported by case-parents. Case-children were less likely to be currently breastfeeding (AOR 30.3, 95% CI 2.0–1000.0). Five (10%) case-patients and no control-patients died. Multiple causal pathogens were identified.ConclusionsDuring this diarrhea outbreak in a country with a national program to prevent mother-to-child transmission of HIV, ill children were less likely to be breastfed and more likely to have been exposed to environmental factors associated with fecal contamination. These findings underscore the importance of adequate access to safe water, sanitation, hygiene, and nutrition education among populations using breast milk substitutes